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From: johnb@srchtec.UUCP (John Baldwin)
Newsgroups: comp.lang.c
Subject: Re: Operations on pointers to void.
Message-ID: <174@srchtec.UUCP>
Date: 14 Aug 90 21:40:57 GMT
References: <1990Aug10.165644.9238@zoo.toronto.edu> <482@array.UUCP> <1990Aug12.231202.23826@druid.uucp>
Organization: search technology, inc.
Lines: 27

In article <1990Aug12.231202.23826@druid.uucp> darcy@druid.uucp
  (D'Arcy J.M. Cain) writes:
>know that the data can be any type but we want to treat it as bytes.  Perhaps
>we need a new type which acts like void * but allows pointer arithmetic based
>on the smallest data type supported by the system, usually (but not always)
>a byte.

There is a simple fix to this: you can operate on void pointers by casting
them to a useful type.  For example, perhaps you are writing a function foo()
which can take a pointer to anything, and for some (unspecified) reason,
you want to "bump" the pointer up three bytes....

SOMETYPE   foo( void *myptr, size_t someval, ... )
{
      .
      .

   *((char *)&myptr) += 3;

      .
      .
}
-- 
John T. Baldwin                      |  johnb@srchtec.uucp
Search Technology, Inc.              |  johnb%srchtec.uucp@mathcs.emory.edu
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